1. Field of the Invention
The invention relates to peripherals which are connected to an upper apparatus through a USB (Universal Serial Bus) interface and, more particularly, to peripherals for realizing multi-function.
2. Related Background Art
An upper apparatus (hereinafter, referred to as a PC (personal computer)) having a USB-connecting function can be connected and disconnected to/from peripherals in the state where the PC operates (state where a power source is ON) and, further, can be connected in parallel to a plurality of peripherals. Therefore, since the USB-connection is easily detachable and a system can be relatively freely constructed, the USB-connection has been widespread. The peripheral added by the USB-connection is recognized by the PC at the moment when it is physically connected to the PC. The PC which recognized the peripheral searches for a driver of the recognized peripheral from drivers which it already has and makes device definition by the searched driver in order to control the peripheral.
As a connection control function of the peripheral mentioned above, an inserting/removing function of the peripherals called a “plug & play (PinP) function” has been known. The plug & play function is realized as will be explained hereinbelow. When the peripheral is USB-connected to the PC, the PC recognizes the USB-connected peripheral (device), automatically searches for a necessary device driver, and activates the corresponding driver, thereby enabling the added peripheral to be used. Specifically speaking, when the PC detects the USB-connection of the peripheral, a bus for USB-connecting the PC and the peripheral is reset, and after the bus resetting, the PC and the peripheral start communication called a “control transfer”.
In the control transfer, the peripheral notifies the PC of information called a device descriptor necessary for the device definition. Function information indicative of functions of the peripheral is shown in the device descriptor. The PC specifies the peripheral as a communication partner destination on the basis of the function information indicative of the functions of the peripheral shown in the device descriptor, makes the device definition for allocating an address called an “end point” to the specified peripheral, and starts USB-communication with the peripheral.
Multi-function peripherals (hereinbelow, referred to as MFP) having a plurality of functions such as scanner function, printer function, facsimile (FAX) function, and the like have been widespread as peripherals. Also in the case of USB-connecting the MFP to the PC and making USB-communication, the PC is notified of the device descriptor showing the plurality of functions provided for the MFP by the control transfer.
For example, as shown in JP-A-2001-222503, in order to select a desired function from the plurality of functions shown in the device descriptor, the PC which received the notification issues a switching command of a connecting construction (vendor request) called a “configuration” and makes the device definition.
In the conventional system, however, since the dedicated driver for selecting the desired function from the plurality of functions and issuing the switching command of the connecting construction is needed and it is necessary to develop such a dedicated driver and install it into the PC as mentioned above, they cause a problem.